The closest prior art can be found in U.S. Pat. No. 4,916,457. This patent by two of the three inventors of the instant invention is directed to a similar type antenna which teaches a printed circuit cavity-backed crossed-slotted conductive element having two legs of each slot coupled by stripling feeders to a radio communication device. The feeders supply the radio frequency signal with a 180 degree phase shift in order to cancel cross-coupling from one leg to another around the intersection. The conductive element and the stripling feeders are mounted on separate substrates which are sandwiched together with other elements to provide shielding and mechanical protection. The crossed-slot design reduces space and structure required for mobile application while achieving good performance. When mounted in an array, the crossed slot antenna may be directionally tuned to a specific satellite/frequency/direction via pin diode phase shifters.
Additional prior art related antennas can be found in the references cited in the above referenced United States patent.
The instant invention is an improvement to the type of printed-circuit crossed-slot antenna taught by the above referenced United States patent.